Natural convective MHD flow of a viscous incompressible fluid along a vertical plate is discussed with the effect of variable electrical conductivity and heat generation under the action of transverse magnetic field in porous medium. It is supposed that there is an internal heat generation along the plate that decays exponentially while electrical conductivity of the fluid is a function of fluid temperature. The process of similarity transformation is used to transform the partial governing equations into ordinary. Considering fluid flow of low Prandlt Number {Pr << 1}, numerical solutions and results are obtained using Runge-Kutta method while Shooting method is used to find the missing initial conditions. The results are used to plot velocity and temperature profile near the plate, and variation of skin-friction and heat transfer at the plate for various values of physical parameters used. The results show significant effects of fluid electrical conductivity and medium porosity on the flow and heat transfer in presence of transverse magnetic field and heat generation.